This invention relates in general to fluid spray systems, and more particularly relates to a spray gun for use with a variety of viscous and semi-viscous materials such as paint, plaster, acoustic dry wall material, waterproofing, fireproofing and mortar for stucco application.
Various types of spray guns have been provided for applying fluid materials to walls, ceilings and other building structures and surfaces. Many of these prior spray guns are difficult and inconvenient to operate. Thus, to turn such a gun off the operator must shut the material pump off at the same time the material flow valve is closed. If the pump does not shut down when the valve is closed the hoses can rupture and blow. The operator must also try to simultaneously turn the pump on when the air valve is opened. Other problems are that typical existing spray guns normally require the use of both hands for operation, and this results in making it more difficult to spray in confined spaces such as closets, underneath stairwells and the like. Existing spray guns also are vulnerable to breakage or going out of adjustment, such as when the gun is accidentally dropped. Moreover, after a gun is shut down it is difficult to re-establish the same spray pattern when turned back on in that the spray pattern is dependent on the number of turns of the flow valve to shut it off. The operator must remember to open the valve up to the same number of turns, otherwise the same spray pattern will not be achieved for resuming the spraying operation.